1960 Johnson 10hp struggling at mid range

[jgaier]

Hi guys, first time posting here but I have been reading through many of the forums and have been loving what I have learned so far. I just purchased a 1960 Johnson 10hp QD-21 S that I am really excited about but it is struggling to go from low to high. It is acting like it is missing a lot or starved of fuel. I have not done much to it yet but I have replaced the lower gear oil, plugs with J4C (it had J8C from previous guy) set the initial carb settings to 1 1/2 out for low speed and 3/4 out for high speed and then slowly turned in until it sputtered and then turned slightly out. The guy i bought it from said he did a carb rebuild last year and replaced all fuel lines and it ran well last year. It seems to idle OK and does really well at high speed but really struggles to get up to high.
So my questionis whether it is a carb tune, or does it need a carb clean/rebuild or is it possibly the coils? I have attached 2 videos at the link below for you to look at so you can see what I am talking about. I have not looked into compression or spark testing yet as I thought you guys might have some great suggestions.

https://drive.google.com/folderview?id=12L01DnPqduk0k6jSA3UZiXbaKGK5MdYy

Thank you for your help and time.

 

[atucker1]

The drive link says it isn't viewable to the public, FYI.

I'm not the most experienced with these but I figure if he did rebuild the carb last year, unless he ran it with pretty old gas AND then left it in all winter the carb should be ok.

The video would help here but my thought is ignition. I had a small outboard with a similar problem and it was that the points gap was a little bit off. Idle was fine but moving up to speed it would start to miss-fire and smoke a bunch and it was that at that certain throttle setting the timing advance led to the timing of the points being a bit off. I readjusted the points and it ran better. Replacing them probably would have helped even more.

Similarly, the 1960s Johnsons (I know the 5.5 and I assume the 10 since they were similar) had coils that cracked/worn out with time, possibly leading to ignition issues. This website here details the repair for that: https://outboard-boat-motor-repair.com/Evinrude Johnson 5.5 HP 1954-1964 Ignition System Tune-up.htm

Just my guess, unless anyone else has a better idea could be worth your while to take a look at the ignition components.

 

[jgaier]

Sorry about the private like to the videos, I just updated that.

 

[lindy46]

Well, it is idling poorly so I'd rebuild the carb and make sure to clean the idle circuit underneath the little freeze plug on the top of the carb. Then I'd check under the flywheel for condition of coils and clean and set the points. It almost sounds like its struggling to fire on both cylinders.

 

[jgaier]

I will look into rebuilding the carb, is there a specific kit anyone can recommend that has everything I need? I read somewhere on this forum that they recommended a certain kit but I can't find the post again for the life of me. It seemed like the one they recommended came with the float and a few other parts that others don't.

 

[Crosbyman]

don't worry about a kit for now just do a good cleaning job work carefully and don't break the main gasket

check coils and redo all electricals if never done

 

[oldboat1]

There is a nozzle that runs up in the middle of the carb -- needs to be squeaky clean (run light wire through the openings). Also be sure the gasket is in place at the bottom of the nozzle (bottom of the bowl). Additionally, be sure there is no air leak at the glass filter bowl -- may need to replace the rubber gasket at the top. You might try it without the sintered filter in case the filter is clogged.

 

[lindy46]

Carb kit 439071. There will be extra parts as kits contain parts for more than one motor.

 

[racerone]

Run with a timing light to see which cylinder is missing.----Or pull recoil off , remove plate to look at the ignition coils.----You can't blame the carburetor for everything on an outboard.

 

[jgaier]

Thank you everyone who has commented so far. I removed the recoil and looked at the ignition coils and to my surprise, they looked really good(from what i could see) they definitely were replaced at one time and i took some pictures for you guys at the link below. I think i will leave this alone until I get it running again and put a spark light on it to see if there is a spark issue.

I then removed the carburetor and took it apart. When i was removing it i noticed the two nuts that hold the carburetor to the engine were just more than finger tight which i would suspect could cause a bad air leak. I preceded to removed it and then disassembled it. It is very clean inside and has an updated float in it but it was not sitting level to the body.

I noticed that the slow speed jet has a very slight bend at the tip, i tried to get a picture and have it int he link below.

I also noticed that there was not any washers or anything with the high speed jet packing nut. It was also leaking gas and would rotate when the engine was running. Would this come in the rebuild kit? I have a picture of it also.

When i first got the boat about a month ago i put in new gear oil. I decided to check it today since i will be ordering parts and it looked milky already. I also have pictures of this. What seals will i need to fix this? I know nothing about the lower units.

It looks like the kit does not come with the seal for the glass bowl. do you know the part number for that?

I am confused when i look for parts because the boat years only go back to 1968? What am i missing?

https://drive.google.com/open?id=12L...UZiXbaKGK5MdYy

Thank you again for all of your help.

 

[oldboat1]

couple of comments -- the high speed needle is held in place with a jam nut that compresses the needle washers. Try and inspect the bowl gasket without dislodging it or breaking it. I've used some permatex on some that were slightly damaged, so that may be a fix if needed (fuel proof sealant). You can straighten the tip of the l.s. needle if very careful. Rotate the beveled part on a hard, flat surface.

 

[jgaier]

I just ordered the carb kit from iboats, do the needle washers come with the carb kit that the jam nuts compress against?

 

[oldboat1]

Yes. Otherwise, can be obtained at any shop. ("needle valve packing washers", pn307583)

 

[jgaier]

oldboat1 thank you.

 

[oldboat1]

You're welcome. Buy a couple of quarts of 2-cycle, and they might throw some in (best to have a supply in the tool box). Hope you get it up and running!